Question

Problem 2. Determine if the following reaction is spontaneous under standard conditions. (more than 2 reactions may be required) Ni(s) + 2 Ce4+(aq) → Ni2+(aq) + 2 Ce3+(aq)

Answer 1

Reduction potential of Ce4+/Ce+3 is 1.70 V, and Ni +2/Ni is (-0.23 V) . reduction potential value is more means it is oxidigsing agent. So Ce4+ will oxidise Ni to Ni+2

another reason is if we calculate gibbs free energy of this system it gives - ve . So processes is sponteniuos.

change in gibbs free energy = gibbs free change in Ce4+/Ce+3 - gibbs free change in Ni +2/Ni

= -nFE(ce4+/3+) - (-nFE (ni/ni+2)

= - 1*F*(1.70) - { -2*F*(-0.23)}

= -2.26 F

gibbs free energy is negative is processes is spontenious.